1. Field of the Invention
The present invention relates to a pointing device, and more particularly, to a pointing device using two linear sensors and fingerprints to generate displacement signals.
2. Description of the Prior Art
A pointing device such as a mouse is used to generate pointing signals to control movements of a cursor on a display device. A prior art pointing device commonly comprises two or three buttons installed in its housing to input button signals. The pointing device is commonly used to scroll a window in the display device. The scrolling of the window in the display device can be performed by moving a scroll square of a scroll bar on the window to another position. This is done by using the pointing device to move the cursor to the scroll square and then depressing one of the buttons on the pointing device. This action grabs the scroll square, permitting it be moved along the direction of the scroll bar by moving the cursor. The direction in which the scroll square moves indicates the direction in which the window will be scrolled: left, right, up or down.
Please refer to FIG. 1 and FIG. 2. FIG. 1 is a perspective view of a prior art pointing device 10. FIG. 2 is a functional block diagram of the point device 10. The mouse 10 is electrically connected to a computer system 20, and the computer system 20 is electrically connected to a display device 22. The mouse 10 comprises a housing 12, two buttons 14 positioned on an upper side of the housing 12 to input button signals, and a roller ball (not shown) installed on a bottom side of the housing 12 for controlling movements of a cursor on the display device 22.
The computer system 20 comprises a memory 24 for storing programs and data, a processor 26 for executing the programs stored in the memory 24, a button control program 28 stored in the memory 24 for receiving and processing the button signals generated by the buttons 14, and a display control program 30 (such as Microsoft Word) stored in the memory 24 which controls the scrolling of a window 32 displayed on the display device 22 according to the button signals.
Many users find the action of scrolling a window inconvenient as it requires fine positioning of the pointing device and button manipulation to grab the scroll square. This action also involves changing the position of the cursor, which can cause inconvenience if the cursor must afterwards be returned to another location on the display device, or is moved from a preferred position.